Carbon black lubricating grease



Dec. 7, 1954 R. O'HALLORAN CARBON BLACK LUBRICATING GREASE Filed Dec.10, 1952 2 Sheets-Sheet 1 0mm 0mm 05 0mm Ohm 0mm 6mm 2m 02 OE 0Q Om; 0:0m ON Om 0v Clbbor'ne WEAR SPOT, DIAMETER, mm.

Dec. 7, 1954 R. O'HALLORAN 2,696,471

CARBON BLACK LUBRICATING GREASE Filed Dec. 10, 1952 2 Sheets-Sheet 2FIG. 2

4-BALL TEST PERFORMANCE OF STEEL MILL GREASES Exp. grease COMMERCIALALUMINUM GREASE I5 25 4O 6O 80 I00 I50 250 -4OO 2O 3O 5O 7O 90 200 300500 LOAD, Kg.

@sema OHc'mlloran. 5nveac r /z abborne s W 3 aten' t *CKRBONBLKCKEfCBfiICATIN'GfflliEKSE If hanhel: w -s m mu h bla 18 ,r ferable. Ihe--'saturated-ffatty=acid,'.which'replaces Rosemary OHeilloran, RosellePairk,-' Nt*J {to the *oleic acid-pr sume types ofprior art greasecompo- StandardOil Development Companfl 'aCOrptiia'tibh of sitions, isused in proportions-of '0.5'-t'o':4 preferably Dlaware abou and "thesulfurized fatty oil (which forms =the h J n I, v pa eatremegpressar'eagentisr'use in proportionsswAppllcatlomDecember=;-1952a'SerlalNMSZSQEZ 3f ltb%. l%'t5%,epfefblylabb t. Io-10,%.' .Alsoitais I v l era e3hatrtrieester ofphosphoricacid, sufch"as tri-- o843laims. )(Cl-- 252-:22) y ;.ph s j s-'trib tyl:fihQsfihhte;tbe g "ort-ions-of"' O.'-5' 7 2,-"preferably"-about.1%. Tri- I I Vcresylpho'spha'teordinarilyispreferred over tributylphos- The presentinvention. relates. to an improved Jri-bripliatefor -thispurpose. catingg're'asecomposition anfd"pa'rtictllarlyzto'a carbon -"A-' s'eries-of'te'sits-rw'efc made iis'ingivario'tls combinablack-alurninum soap greasewh h iiita l fo tions of mineral "oil bas ad varying proportions a a hvi dugtrial equipment siieh channel type-barb n blabk offinep'aitticlesizesold" 'r the like where high temperatures *heayyunitgpresthe tradename Sup rba'FB1ackP l Eachbfjthe posurecohditionsareencountered. v siti'ofnsreontainedabout"9'%ffdf" l l l pe mIt has been suggested previou' s'ly in applieat' "Serialthough-proportions of 15i-to 15 %;'of =sulfurized {sperm "oil No."218;260' 'fi1ed;March-29, 195-1;- no'w Pa-tentf No. r dtlierlflirizedor ph ph -i lfl rize f y' ilis s ch 2,653,1311,by-the presentinventon *t-hat'a'. combintati'o'n as laid oil, bttonsbe'sdoil and=the1ike "can p y ofalumi'nunr soap arid ca'i'bon blackasthicken'gziageiits with reasonably satisfactoryres'ults. I in lubricating bil-results in' the forrn'ationjof wsnperim 'llr' ach' ase. a standardcommercia fi lii fl gr'ea-s' for heavy industrialapplications o thetypefmenp'r'evio isl'yIpiepaIedf was usedf-a's' 'the soapfingredientffof tioned above. Accofdin the 'pre'seht ention it hasthethickener'andduSQHieiwses 2% of t h fhya iQ t been -'four'-id"*that"greases im reed'yil and oth'r adfish-oil acids 'mentioned above wereemployed. The vantage'ous properties rnaybefobtamedibyisiibtitut giancontained 2%' --'of-"oleic"acid. An additional in en't, acid treatednrineral bas'e'lubricating oil for theusu a l-black trio'resylpho's'phate ro Iortions of 1%, was'"'added in oil =emplo'yed"i1r--greasof this typeaiid' th'at furt-lfer i'meach-composition, 'lltperce'ntagesjgivenare byxweig'ht, provementma be inediby using asmalpercentage base on thejtbtal composition. :fThe greasesfdesc iibed oi-saturated fattty 'a d- 'of jthe' cwtc 0 0 range-*in' eomher in-were-"li m 'de y h l l ndin P "'e ut bination with the sea lane;carbon black."135. s ib i e, p e appl' on. ri N -'-.21 8;26,

It has been known in the prior art to use extreme mentioned-above. I rpressure agents in' -lreavy duty l-ub'ricatin g-reasesof the -lt*'will=befnoted fr'o'mjthe table below that the greases type underconsideration. zflommonlwarsulfurized fatty containing the'f'sfatitratedfatty i'a'cid allhad a droppingoil and other extremepressure additives, which may inptiiritab'ove 500 F."Theresultsofqtheselseveial'expericlude bleic acid in some cases,have'bieen added ,to lu'b'ri ments' are'jndicatediinfTa h L Th P358 4 3D Sfp eating greasesof--the-carbon blac "tyltve -for somefopr-aration'-test-'refrred to'consistsofcollectingand weighing tio'ns. iflha'snow been-discovere owever, th a ,a'il'ery the oi1=express d1fr0m ag.,.. g'rea'se'f'sa'mple thr ugh substantialincrease'in"consistency-'-is dbtainedbyoorm double 050,*filterffiperaftr ZOj-hOHrS.l nden-I00 bining an acid treated oil withthe carbon black and prsf'i: g? z'=pre'ssnre-*in a=meta1- cylinder.

TABLE I ICC is betwee sanit ze preferabiy aiionr 10 to 12% ,aand

ma be eitherfacetylerie carbon "'black' or 'channehblack 'Xtur'ethereof.'Fori optimum; extreme pressure owever; channel blackerfatleast asubstantial Experimental steel mill greases containing 9%:asalfsfspermoil, 2% oleic acid, 1% trictesyl phosphate eu' eiua 'Dropping"Worked"Pressure Soap Solution Mineral Oil Base -Blaek, 2;}: Point, Pen., OilSop Percent g F. 1 'mmJ/1O "Percent I 2.8% Commercial Aluminum StearateCrude Distillate Oil... 10 Lab.-." 468 Pass 38. II do do 10 do 12 V AcidTreated l, 10

S. S. U. at 210 F. V 2.8% Commercial Al. Stearate+2.0% Hyd0 10 Lab 500+Pass 38.

drofol Acid 53. VI d0 500+ Fail 33. VII do 500+ Pass 38. VIII. do 1 500+Pass 33. IX... Commercial Acetylene Bla 500+ 361 8.6.". Fail 33. DesiredLevel of Performance 500+ 380 Max. 5.0 Max. Pass 33.

1 Contains no oleic acid.

2 10% acetylene black.

1 5% Superba. (channel) black plus 5% acetylene black. aluminum soapthickeners and a further and substantial improvement is obtained byincorporating saturated fatty acids of the C14 to C20 range. Forexample, fatty acids sold commercially under the trade names HydrofolAcids 53 and Hydrofol Acids 54 are used in the extreme pressurecomponent, replacing oleic acid where the latter has previously beenemployed.

Hence the composition of the present invention comprises a majorproportion of acid treated petroleum base lubricating oil containingbetween 1 and 5% by weight of aluminum soap of predominantly saturatedfatty acids of the C12 to C22 range. The preferred aluminum soap isaluminum stearate and it is preferably used in proportions of about 2 to3%. The carbon black content It will be noted from the above table thatwhen the saturated fatty acids and the acid treated oil were used toreplace oleic acid and the crude distillate oil, respectively, thepenetration improved from 405 mm./ 10 in a laboratory batch to 343 mm./10 other ingredients and processing being the same. In a pilot plantbatch of grease the penetration value of the grease containing theHydrofol (saturated) acids was only 321 mm./ 10. The differencerepresents a considerable increase in yield value. Definite improvementwas obtained by substituting the saturated fatty acid for the oleic acidin the laboratory product also (compare V and VII of Table I). Thesubstitution of saturated for unsaturated fatty acids brought the workedpenetration in the standard ASTM test apparatus from 375 mm./ It) downto 343 mm./ 10 with the sameacid treated base oil.

Inasmuch as the cost of the soap and carbon thickeners for these heavyindustrial greases is a very substantial item in their production it isapparent that substantial savings may result from the substitution ofacid treated oil for conventional black oil, because of the improvedyields mentioned above. Even greater savings result when the saturatedfatty acids are employed in place of the conventional oleic acid. Acombination of these features results in very substantial improvementsin yield without any sacrifice in quality.

Greases containing both oleic acid and saturated fatty acids were testedalso for extreme pressure performance. Both of them carried a load of 38pounds in the standard Timken test machine. This is regarded as entirelysatisfactory. The commercial grease listed in Example IX of Table I didnot carry even 33 pounds which is considered minimum for satisfactoryperformance. It had a worked penetration of 361 mm./ 10 which isacceptable although rather soft, but its oil separation was excessive,8.6% as compared with 2.8% and 3.2%, respectively, for the laboratoryand pilot plant batches of the present invention. As noted in the tablea maximum amount of oil separation of 5% is acceptable. The use ofstraight channel black (EX. I, V, VII) results in superior Timkenmachine performance as shown in the table. However, the high temperatureproperties of this blend, as shown by high temperature pressureviscometer runs, are not equivalent to those where at least a part ofthe channel black is replaced by acetylene black. These runs are showngraphically in the drawing, Figure 1. It may be seen on the figure thatEx. VIII, the grease of invention (containing 50-50 channel andacetylene black) is equivalent in bodying properties to straightacetylene black grease (Ex. VI) and far superior to straight channel(Ex. VII). Reference to the table will show that the extreme pressureperformance of Ex. VIII is satisfactory, showing a Timken pass at 38.

Extreme pressure properties of the grease of the invention are alsoshown by its performance in the 4-ball wear test. This test wasdeveloped by the United States Navy and has been described in variousreferences. The performance standards have been set up by Aluminum Co.of America and published in their ML-792 (Revised April, 1951)Specification covering a multipurpose extreme pressure grease. Thegrease of the present invention is compared with a typical greasemeeting this specification below:

Complete load versus wear-spot curves for these two greases are plottedin Figure 2.

It will be understood that various modifications may be made in processand product without departing from the spirit of the invention. Themethod used for preparing the greases described above was to add thefatty acids directly to aluminum soap in oil (soap concentrate or greasebase), heat until fluid (250300 F.), pan cool to ambient temperature andthereafter to stir in the carbon black, followed by adding thesulfurized sperm oil and the other extreme pressure ingredients.

What is claimed is:

l. A lubricating grease composition comprising a major proportion ofacid treated petroleum base lubricating oil, 1 to 5% by weight, based onthe total composition, of aluminum soap of predominantly saturated fattyacids of the C12 to C22 range, 5 to 25% of carbon black, 05 to 4% ofsaturated fatty acid of the C14 to C20 range, and 5 to 15% of asulfurized fatty oil as an extreme pressure agent.

2. Composition according to claim 1 wherein the aluminum soap isaluminum stearate.

3. Composition according to claim 1 wherein the carbon black isacetylene black.

4. Composition according to claim 1 wherein the carbon black is achannel black.

5. Composition according to claim 1 where the carbon blacks are mixedacetylene black and channel black.

6. Composition according to claim 1 to which is added 0.5 to 2% of atri-ester of phosphoric acid.

7. Composition according to claim 1 to which is added about 0.5 to 2% oftricresyl phosphate.

8. A lubricating grease composition consisting essentially of about 73to 76% by weight of acid treated mineral base oil of 50 to S. S. U.viscosity at 210 F., about 9% sulfurized sperm oil, about 2 to 3% ofaluminum stearate, about 5% channel black, about 5% acetylene black, 2%saturated fatty acids of the C14 to C20 range, and about 1% tricresylphosphate.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,367,355 Kaufman et al. Jan. 16, 1945 2,480,647 Gurd et al.Aug. 30, 1949 2,487,260 Morway Nov. 8, 1949

1. A LUBRICATING GREASE COMPOSITION COMPRISING A MAJOR PROPORTION OFACID TREATED PETROLEUM BASE LUBRICATING OIL, 1 TO 5% BY WEIGHT, BASED ONTHE TOTAL COMPOSITION, OF ALUMINUM SOAP OF PREDOMINANTLY SATURATED FATTYACIDS OF THE C12 TO C22 RANGE, 5 TO 25% OF CARBON BLACK, 0.5 TO 4% OFSATURATED FATTY ACID OF THE C14 TTO C20 RANGE, AND 5 TO 15% OF ASULFURIZED OIL AS AN EXTREME PRESSURE AGENT.